Tabla de Contenidos
Dental enamel is the outermost layer of the tooth. It is a bright, accessible and visible layer. It is made up of 94% small crystals of a substance called calcium phosphate and 4% organic material, mainly proteins. The composition of enamel makes it the hardest tissue in the human body.
Like tooth enamel, the egg shell is made up largely of calcium, which comes in the form of a compound called calcium carbonate; it also contains proteins and lipids. Since eggshells are similar in composition to tooth enamel, they can be taken as a benchmark for what happens to teeth when exposed to a highly acidic environment in the mouth. Such an environment is fostered by oral bacteria capable of producing acids from sugars in the diet. This causes the pH to drop and the tooth enamel to demineralize.
For all of the above, an experiment can be carried out at home in which the effect of acids on a surface similar to that of teeth is evident. This will help you understand the consequences of allowing sugary and acidic substances to accumulate on your teeth.
Materials
For this experience you need:
- 2 hard-boiled eggs, that is, previously cooked without losing their shell.
- 350 ml of a sugary, fizzy drink, such as soda.
- 350 ml of white vinegar.
- 350 ml of water.
- Two transparent glasses large enough to each hold an egg.
- Indelible marker.
- Film or aluminum foil.
- Elastic bands.
Problem question
Before starting the experience, it is important to ask the question that you want to solve. It is recommended that the question be verifiable with the expected results and not be answered by a yes or no. Some suggested questions for this experience are:
- What are the effects of acidic and sugary substances on a tooth-like surface?
- Are sugary or acidic substances harmful to a tooth-like surface?
- Are there differences between the effect of sugary substances and that of acidic substances on a surface similar to that of teeth?
Statement of the hypothesis
The hypothesis, in this case, corresponds to the preliminary answer to the problem question. This answer is formulated before carrying out the experience and can be modified at the end of it. Since this is a guess, you can imagine what vinegar or sugary drink will do to an eggshell and how this effect would be similar to what you might see on your teeth.
Procedure
- Label each glass according to the liquid you will be adding (water, vinegar, or sugary drink).
- Carefully add one hard-boiled egg to each glass.
- Pour over each egg the corresponding liquid according to the name with which you marked each glass.
- Leave the eggs inside each glass for 48 hours at room temperature.
- After this time has elapsed, remove the hard-boiled eggs from each glass and record your observations in a table like the one suggested below.
Results and analysis of the results
To record your observations, you can arrange and fill in a table like this one.
| Sample | Effect on the peel after 48 hours |
| egg in water | |
| Egg in sugary drink | |
| pickled egg |
In experience it is expected that the most noticeable effect on the shell is observed in the egg dipped in vinegar. In this case, the acetic acid in the vinegar reacts with the calcium carbonate in the peel, releasing carbon dioxide in the form of bubbles during the process. The acetic acid breaks down the calcium and essentially eats away at the shell of the egg.
For the analysis of results, the following questions can be asked:
- Which of the substances most affected the structure of the eggshell? Because?
- Why do you think an egg dipped in a sugary drink was used in this experiment?
- What do you think is the function of the egg submerged in water in this experiment?
- If tooth enamel is similar to eggshell, based on the results observed in this experiment, which beverages do you think are best for teeth? because?
Sources
Núñez, D., García L. Biochemistry of dental caries . Havana Journal of Medical Sciences , 9 (2): 156-166, 2010.
